<?php
require_once 'duck.php';
require_once 'duckBehavior/fly.php';
require_once 'duckBehavior/quck.php';
//肥鸭
class PangDuck extends Duck{

    public function say()
    {
        echo $this->flying();
        echo $this->qucking();
    }

    //睡觉
    public function sleep()
    {
        return  '<br>i am sleeping now';
    }
}